How do scientists extrapolate the total number of species on earth ?

Explanation

To understand how scientists extrapolate the total number of species on Earth, we can break down the process into several key steps:

### Step-by-Step Solution:

1. **Selection of an Exhaustively Studied Group**:
Scientists begin by selecting a specific group of organisms that have been studied in detail. This is often a group like insects, which are abundant and diverse.

2. **Calculation of Species in the Selected Group**:
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